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  • JavaScript对象添加、删除、修改对象的属性

    https://www.cnblogs.com/goweb/p/5357640.html

    利用动态特性

    function Person(){};
                var person = new Person();
                person.name = 'yy';
                person.gender = 'girl';
                console.log(person.name+','+person.gender);//yy,girl
                delete person.name;//删除属性
                console.log(person.name);//undefined
    //            变式
                function Person(){};
                var person = new Person();
                person['name'] = 'yy';
                person['gender'] = 'girl';
                console.log(person.name+','+person.gender);//yy,girl
                delete person.name;//删除属性
                console.log(person.name);//undefined
    

     

    构造函数中this

    var Person = function (){
                    this.name = 'yy';
                    this.gender = 'girl'
                };
                var person = new Person();
                console.log(person.name+','+person.gender);//yy,girl
    

     

    原型中添加属性

    var Person = function (){    
                };
                Person.prototype.name = 'yy';
                Person.prototype.gender = 'girl';
                var person = new Person();
                console.log(person.name+','+person.gender);//yy,girl
                console.log(person['name']+','+person['gender']);//yy,girl
    

      

    字面量添加属性

    var person = {    
                };
                person.name = 'yy';
                person.gender = 'girl';
                console.log(person.name+','+person.gender);//yy,girl
                console.log(person['name']+','+person['gender']);//yy,girl
    //            另一种写法
                var person = {
                    name: 'yy',
                    gender: 'girl'
                };
                console.log(person.name+','+person.gender);//yy,girl
                console.log(person['name']+','+person['gender']);//yy,girl
    

      

    封装extend方法

    var p1 = {};
    var p2 = {name:'yy',gender:'girl'};
    
    p1.extend = function(obj){
        for(var k in obj){
             this[k] = obj[k];
                    }
         }
    
    p1.extend(p2);
    console.log(p1.name+','+p1.gender);//yy,girl
    console.log(p1['name']+','+p1['gender']);//yy,girl
    

     

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  • 原文地址:https://www.cnblogs.com/qianjinyan/p/8921259.html
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